Cooled surgical instrument



Oct. 3, 1967 HIRSCHHORN Re. 26,276

COOLED SURGICAL INSTRUMENT 2 Sheets-Sheet 1 Original Filed Jan. 29, 1962INVENTOR MAX L. HIRSCHHORN BY flak. $1.4, W rJ M ATTORNEYS Oct. 3, 1967M. HIRSCHHORN Re. 26,276

CGOLED SURGICAL INSTRUMENT Original Filed Jan. 29. 1962 2 Sheets-SheetINVENTOR MAX L HIR SCHHOR N dw wmzjlw yM ATTORNEYS United States PatentOfiice Re. 26,276 Reissued Oct. 3, 1967 26,276 COOLED SURGICALINSTRUMENT Max L. Hirschhorn, 5601 13th Ave., Brooklyn,N.Y. 11219Original No. 3,093,135, dated June 11, 1963, Ser. No.

169,266, Jan. 29, 1962. Application for reissue May 28, 1965, Ser. No.463,068

7 Claims. (Cl. 128303.1)

Matter enclosed in heavy brackets appears in the original patent butforms no part of this reissue specification; matter printed in italicsindicates the additions made by reissue.

The present invention relates to surgical instruments and moreparticularly to a cooled surgical instrument.

At the present time surgery is performed with knives, probes, biopsyscoops and other instruments which are sterilized and then allowed tocool to room temperature. Necrotizing thermo coagulative devices arealso used. Recent medical investigations have shown the value in certainoperative techniques of cooling parts of the body. For example, shockand hemorrhage may be lessened in brain surgery if the blood enteringthe brain is cooled to approximately 60 F. by circulating it throughexternal cooling means. In other operative techniques the entire body iscooled so as to reduce the body metabolism or ethyl chloride is sprayedon the skin to freeze it by evaporation prior to opening a drainingincision.

It is an objective of the present invention to provide a surgicalinstrument having a cutting edge or tool which is considerably cooledbelow ambient room temperature. The cooled edge acts to lower the flowof blood, lower pain, and preserve the viability of the tissue byreducing its local metabolic needs below the shock stage.

In accordance with the present invention a surgical instrument isprovided having a handle cooled by its own internal refrigeratingsystem. A plurality of metal heat conductive surgical [instruments]tools may be removably inserted into the end of the handle. Preferably,the handle has an automatic temperature sensing and control apparatus sothat the temperature of the surgical [instruments] tools may bepredetermined and held constant.

Other objectives of the present invention will be apparent from thebelow detailed description of a preferred embodimentalong with theaccompanying drawings, in which:

FIGURE 1 is a side sectional view of the surgical instrument showing theinternal construction of the surgical handle;

FIGURE 2 is a perspective view showing an alternative to the male end ofthe handle of FIGURE 1;

FIGURE 3 is a front view of the handle of FIGURE 1;

FIGURE 4 is an electrical circuit diagram of the power supply for thehandle;

FIGURE 5 is a perspective view showing a surgical blade with its handleportion adapted to fit into the male end shown in FIGURE 2;

FIGURE 6 is a surgical probe with its handle portion adapted to fit intothe male end of FIGURE 2;

FIGURE 7 is a perspective view of a triangular biopsy scoop with itshandle portion adapted to fit into the male end shown in FIGURE 2; and

FIGURE 8 is a perspective view of a surgical knife with its handleportion adapted to fit into the male end shown in FIGURE 1.

The surgical handle shown in FIGURE 1 consists of a body member 1 whichis preferably of a heat insulative material, for example, a plasticthermosetting material such as a phenolformaldehyde resin which has lowheat conductivity and may be sterilized by ordinary steam hospitalsterilizing apparatus. The insulative body member 1 has within it asolid, rectangular and elongated metal heat conductive rod 2, preferablyof silver, copper, or copper alloy. Situated above the rod 2 and inphysical contact with it are a plurality of Peltier elements 3. The coldjunction 5 of the Peltier elements are in contact with rod 2, while thehot junction 4 is directed away from rod 2.

In the Peltier effect a direct current passes through a junction of twodissimilar conductors and heat is absorbed or generated at the junction,depending on the direction of current. A number of combinations ofdissimilar conductors exhibit the Peltier effect including two differentmetals, a semi-conductor with a metal, a p-type or 11- typesemiconductor with a metal, and a p-type semiconductor with an n-typesemi-conductor. Although all such combinations are capable of exhibitingthe Peltier effect, preferably the combination has large thermoelectricpower, low thermal conductivity and high electrical conductivity. Inaddition, the materials should preferably be inexpensive, readilyformable and easy to solder and weld.

The hot junctions of the Peltier elements are physically connected, forexample by soldering, to a plurality of temperature conductiveperforated fins 6. These fins are, for example, sheets of a copper alloy,6 of an inch thick having a large number of perforated holes throughthem. The top and sides of the fins are held within a tube formed by theinsulative body 1. On the side of body 1 near the knife end of thehandle (side A in FIGURE 1) a blower fan 7 driven by an electricalsubminiature motor 8, takes in air through opening 9 and blows that airthrough the perforated fins 6 Within the tube formed by body 1 and outof the air exhaust 10. Blower 9 may be replaced by an external source ofpressurized air, for example, a small pressure line connecting thehandle to an air pump.

In the smaller handles made in accordance with the present invention,the blower fan 7 may be eliminated ,and the heat dissipated into the airby the fins physically attached to the hot ends of the Peltier cells.

On the side of the handle opposite the blower (side B in FIGURE 1) atemperature sensitive device 11 is in physical contact with rod 2. Thistemperature device includes an electrical thermocouple or thermistorwhich is inserted in a cavity in rod 2 so as to touch the sides of thecavity. Temperature sensitive device 11 is electrically connected to atemperature control dial 12 on the side B of the surgical handle. Dial12 electrically controls the amount of power flowing to the Peltiercells 3, for example by means of an electric potentiometer. Dial 12 andthe temperature sensing device 11 are part of an electrical circuitwhich functions so that a temperature dialed on dial 12 will beautomatically maintained. Similar controls are widely known and are usedin automatic blankets and other devices in which a predeterminedtemperature is maintained by regulating an electric current.

The direct current to the Peltier cells 3 and motor 8 is supplied frombridge rectifier 50 (see FIG. 4). Alternating current is supplied bridge50 through wires 13 which are connected to transformer 14. The primaryof transformer 14 is connected to AC. current source 15. The full-waverectifying bridge 50 changes the AC. current from the secondary oftransformer 14 into DC. current for operation of the Peltier cells.

Other electrical sources may be envisioned for use with the surgicalknife of the present invention. For example, a small battery may beinserted in the end of the knife or the power may be derived from aplurality of silicon solar cells on the face of the handle.

On the side of the handle (side A of FIGURE 1) a male handle end isprovided in the end of rod 2 to permit insertion of a plurality ofdifferent surgical instru- 3 ments. In the embodiment of FIGURE 1 thetip (male end) of the handle comprises a spring button lock 16 and twoscrew groove guides 17. This end enables the surgical [instruments]tools to be screwed onto the end of the handle held firmly during useand to be readily unfastened.

FIGURE 2 shows a variation of the spring button lock and the screwgroove guide which may be utilized with the cooled handle of FIGURE 1.In FIGURE 2 a triangular slot or cavity 18 is cut within rod 2 and amale cone 19 positioned at the bottom of the cavity.

FIGURES -8 illustrate various surgical [instruments] tools which may beutilized with the cooling handle of the present invention. Thesesurgical [instruments] tools are all made of good temperature (heat)conductive material, for example, copper alloy, and their cutting edgesare preferably of a hard sharpenable material such as high carbon steel.In the blade 20 (FIGURE 5) the handle portion 21 has a triangularexternal configuration 22 so as to fit within cavity 18. A female bore23 is cut in the end of the handle portion 21 to fit over male cone 19.The blade 20 has a cutting edge 24 of high carbon steel. The probe 26(FIGURE 6) is of good temperature (heat) conductive copper alloy.Preferably portions of the probe are covered with a heat insulativeplastic material. The external configuration of the handle end of theprobe 28 is triangular and has a female bore portion. In the triangularbiopsy probe 29 (FIGURE 7) the handle portion 30 is triangular and hasan internal female bore.

In the surgical blade 32 (FIGURE 8) the body of the material is of acopper alloy and the cutting edge is of high carbon steel. The handle ofblade 32 comprises a metal rod 34 having two protruding screw tips onits inside surface. The spring button lock 16 of the male end of thehandle of FIGURE 1 has a small hole which snaps over the protrudingtips. In all cases, there is a good physical contact between the rod 2and the surgical instruments, so as to permit the cooling temperature tobe readily transferred.

The primary usefulness of the blade is in operations upon parenchymalsurgery, which is accompanied by capillary bleeding, for example inbrain, kidney and liver operations.

In minor surgery, pain is minimized by the local anesthesia produced bythe instrument, the area kept dry by vasoconstriction, and the tissuemaintained in its cellular vitality.

I claim:

1. A surgical instrument comprising a heat conductive [body having aknife edge in heat conductive relation with the body] surgical tool, aheat conductive rod heat conductively connected to said [body,] tool, aplurality of Peltier cells each having a cold and a hot junctionconnected at their cold junction to the rod, means to connect thePeltier cells to a source of direct current electricity, heat radiatingmetal fins connected to the hot junctions of the Peltier cells, and athermally and electrically insulative handle [comprising the exteriorportion of the instrument whereby the knife edge is] surrounding thePeltier cells and a portion of the rod whereby the surgical too) iscooled for surgical operations.

2. A surgical instrument as in claim 1 and also including means to blowcooling air over the fins.

3. A surgical instrument as in claim 2 wherein the blowing means is anelectric motor having .a shaft and a fan connected to the shaft andwherein the fins are enclosed in a tube having an entrance portion forthe entry of the blown air and an exhaust port.

4. A surgical instrument as in claim 1 in which the heat conductivemetals are copper alloys.

5. A surgical instrument as in claim 1 and also including a temperaturesensitive electrical instrument and a power control device connectedtogether in a circuit and operatively associated with the surgicalinstrument to provide automatic temperature control for the surgicalinstrument.

[6. A surgical instrument as in claim 1 in which the source of directcurrent is an electrical battery in the handle] 7. A surgical instrumentas in claim 1 wherein the heat conductive connection includes means forremovably connecting the rod to the [body] tool.

8. A surgical instrument as in claim 1 wherein a substantial portion ofthe surface of said heat conductive [body] tool is covered with a heatinsulative plastic material. [and the surface of the knife edge portionof said body is heat conductive] References Cited The followingreferences, cited by the Examiner, are of record in the patented file ofthis patent or the original patent.

UNITED STATES PATENTS 2,746,264 5/l956 Keyes 62293 2,984,077 5/1961Gaskill 62-3 3,088,288 5/1963 Elving 128400 X RICHARD A. GAUDET, PrimaryExaminer.

W. E. KAMM, Assistant Examiner.

